Square Feet to Acres Converter
Convert square feet to acres — 43,560 square feet to the acre. Results update as you type; exact factors shown.
One square foot is 0 acres — see the exact factor, not a rounded rule of thumb.
How the square feet to acres converter works
Areas convert through the square metre. Because the inch is exactly 25.4 mm, a square foot is exactly 0.09290304 m², an acre (43,560 square feet) is exactly 4,046.8564224 m² and a square mile (640 acres) is 2,589,988.110336 m². A hectare is 10,000 m² by definition.
Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.
Common area conversions
| From | To | Units |
|---|---|---|
| 1,000 ft² | 0.023 ac | square feet to acres |
| 5,000 ft² | 0.1148 ac | square feet to acres |
| 10,000 ft² | 0.2296 ac | square feet to acres |
| 21,780 ft² | 0.5 ac | square feet to acres |
| 43,560 ft² | 1 ac | square feet to acres |
| 87,120 ft² | 2 ac | square feet to acres |
| 100,000 ft² | 2.2957 ac | square feet to acres |
| 200,000 ft² | 4.5914 ac | square feet to acres |
| 435,600 ft² | 10 ac | square feet to acres |
| 500,000 ft² | 11.4784 ac | square feet to acres |
| 1,000,000 ft² | 22.9568 ac | square feet to acres |
| 2,000,000 ft² | 45.9137 ac | square feet to acres |
Units in this converter and their exact factors
| Unit | Symbol | One unit in square metres |
|---|---|---|
| square millimetre | mm² | 0.000001 square metre |
| square centimetre | cm² | 0.0001 square metre |
| square metre | m² | 1 square metre |
| hectare | ha | 10,000 square metre |
| square kilometre | km² | 1,000,000 square metre |
| square inch | in² | 0.00064516 square metre |
| square foot | ft² | 0.09290304 square metre |
| square yard | yd² | 0.83612736 square metre |
| acre | ac | 4,046.8564224 square metre |
| square mile | mi² | 2,589,988.110336 square metre |
FAQFrequently asked questions about area conversion
How many square feet in an acre?
43,560 exactly.
How big is that?
About the size of an American football field without the end zones.
Where did 43,560 come from?
An acre was one furlong (660 ft) by one chain (66 ft), which multiplies to 43,560.
How many acres is a typical suburban block?
Often a quarter to a third of an acre.
What is an acre in square metres?
4,046.86 m².
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Measurement Institute (NMI) — Australia's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.